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How to UWP Print ListView ItemTemplate

I'm trying to figure out how to print a ListView ItemTemplate using the uwp PrintHelper.cs sample. Everything works, except the print preview does not display items added to the ListView at runtime. I can add other controls such as a textbox, and the print preview will show it, so there must be something peculiar with printing databound ListView items at runtime, but I cannot find any information about it.
<ListView x:Name="ClipboardList"
xmlns:m="using:QuickieEdit.Models"
ItemsSource="{x:Bind ViewModel.MemoryItems}">
<ListView.ItemTemplate>
<DataTemplate x:DataType="m:MemoryItem">
<StackPanel Orientation="Horizontal">
<Button x:Name="MemoryCopyBtn"
Content="Copy"
Click="How to Copy currently selected
MemoryListItem.Text?"/>
<TextBox x:Name="MemoryListItem"
Text="{x:Bind Memory, Mode=TwoWay}">
</TextBox>
</StackPanel>
</DataTemplate>
</ListView.ItemTemplate>

I cannot understand your exact query, but I think you may be facing situation where your ListView does not get updated with the model and hence does not show up while printing. You can use
ObservableCollection<Model> instead of List<Model>
This will solve your problem or if it does not please provide the c# code in detail as well
Cheers

React on user clicking already selected ListViewItem, MVVM

I have a ListView that looks like this, that controls which tab in my application that is opened.
<ListView Grid.ColumnSpan="2" Grid.Row="1" SelectedItem="{Binding Path=SelectedSubstanceName}" Name="listView" ItemsSource="{Binding Path=Substances}" HorizontalAlignment="Stretch" Margin="2" VerticalAlignment="Stretch">
<ListView.ContextMenu>
<ContextMenu>
<MenuItem Header="Lägg till" Command="{Binding AddSubstanceCommand}"/>
<MenuItem Header="Ta bort" Command="{Binding RemoveSubstanceCommand}"/>
</ContextMenu>
</ListView.ContextMenu>
<ListView.ItemTemplate>
<DataTemplate>
<WrapPanel>
<TextBlock Text="{Binding Name}" FontWeight="Bold" />
</WrapPanel>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
I use the SelectedSubstanceName property to detect which tab to open, or switch to, if it's already open.
The property looks like this:
private SubstanceName selectedSubstanceName;
public SubstanceName SelectedSubstanceName
{
get
{
return selectedSubstanceName;
}
set
{
selectedSubstanceName = value;
OnPropertyChanged("SelectedSubstanceName");
if (selectedSubstanceName != null)
{
if (!Tabs.Any(t => t.Identify(selectedSubstanceName.SubstanceNameID, typeof(SubstanceTabsViewModel))))
AddTab(selectedSubstanceName);
else
SelectedTab = Tabs.First(t => t.Identify(selectedSubstanceName.SubstanceNameID, typeof(SubstanceTabsViewModel)));
}
}
}
The case I'm not able to cover is when the user clicks "someSubstance", the corresponding tab is opened, the user closes it, and "someSubstance" is still selected. If the user wants to open it again, he has to select some other substance (which will then be opened), and then click "someSubstance" again. Is it possible to trigger the property even when clicking the same ListViewItem?
I know I could add an event on double-click, but ideally, I want to avoid both events and double-clicks.

I think the problem is that after clicking an item the first time the list's SelectedItem gets set. After clicking the same item the second time SelectedItem won't change because it is already set to that item. What you should do is set the SelectedItem to null after handling the click.

Try to unselect all Items in your ListView after the tab is closed.
YOURLISTVIEW.UnselectAll();
So the next time someone selects an Item there will be a change.

You don't actually want to use the ListView class, but instead simply use the ItemsControl, since it is the most basic way of representing a sequence of elements, but without the extras such as SelectedItem, SelectedValue, etc. that any class deriving from Selector has.
From there, it's merely a matter of how to represent each item in the ItemsControl. The behavior you want is to know when a specific item has been clicked on, which would make the Button class a good candidate, since it handles click behavior through an ICommand interface. Obviously, since you know about DataTemplates and styling in general, you should already know that you can customize how the button looks (visually) without sacrificing the actual behavior (click-handling).
<ItemsControl ItemsSource="{Binding Path=Substances}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Button Style="{StaticResource SomeStyleToChangeItsLook}"
Command="{Binding Path=SelectSubstanceCommand}"
CommandParameter="{Binding}"
Content="{Binding Path=Name}" />
</DataTemplate>
</ItemsControl.ItemTemplate>
</ItemsControl>
public ICommand SelectSubstanceCommand { get; private set; }
private void SelectSubstance(object parameter)
{
// Add the substance that was "clicked" on here however you want to do it.
}
Keep in mind I don't know what framework you are using, so I just gave a general example of how the Command code might look in your view-model. The key to MVVM and using WPFs awesome UI is to always think of what behavior you want and which controls offer that behavior. Ignore how they actually look because that can be changed without losing that behavior.

Using Icons in WPF Database Driven Application Results

I am attempting to make a WPF application. The application needs to use a "list view" to show results of queries to the database. I have been able to successfully create the application (GUI, database, LINQ, etc.), however, the display of my query results appear more "gridlike".
The specifications for the project below show that each record that appears in the results needs to have a green circle icon next to it. I have removed the actual results from the images below to keep the contents of the database private.
I don't have enough Reputation Points to post images, so I posted pictures so a sample/testing domain that I use. You can see screenshots here of the WPF app and code here:
http://digitalworkzone.com/WPF.html
What am I doing incorrectly? Is there something I need to add or modify to my code to be able to get the green circles and more of a "list" style to display my query results?

Understand the WPF content model. http://msdn.microsoft.com/en-us/library/bb613548.aspx
Anything that has a 'Content' property basically behaves in two ways. If the 'Content' is set to something that derives from UIElement, then the class will manage it's own presentation. Anything else, however, will just get .ToString() called, and it's text displayed instead.
What this means in the long run is that everything in WPF can display anything. If you want to show a button in a button, you can. For example:
<Button>
<Button.Content>
<Button Content="This will show as text" />
</Button.Content>
</Button>
The inner button will have text, but the outer button will show a Button because Button derives from UIElement and therefore will handle its own presentation.
In your picture examples above, you have ListBoxes/DataGrids that you want to fill in with graphical information. Try this out:
<ListBox HorizontalContentAlignment="Stretch">
<ListBox.Items>
<Button Content="One"/>
<Button Content="Two"/>
<Button Content="Three"/>
<Button Content="Four"/>
</ListBox.Items>
</ListBox>
Now you have a ListBox that shows Buttons instead of Text. You can take this a step further and contain the items in a stackpanel, for example:
<ListBox HorizontalContentAlignment="Stretch">
<ListBox.Items>
<StackPanel Orientation="Horizontal">
<Button Content="A button"/>
<Label Content="Some text" />
</StackPanel>
<StackPanel Orientation="Horizontal">
<Button Content="A button"/>
<Label Content="Some text" />
</StackPanel>
<StackPanel Orientation="Horizontal">
<Button Content="A button"/>
<Label Content="Some text" />
</StackPanel>
</ListBox.Items>
</ListBox>
Now we have items that contain a layout container (StackPanels, which then contains other elements).
However, if you set the ItemsSource elsewhere, you can actually use a DataTemplate to display the contents. A DataTemplate in effect targets a particular class and lays out it's contents as defined in XAML. Consider:
Code Behind:
public partial class MyWindow : UserControl {
public MyWindow() {
InitializeComponent();
MyListBox.ItemsSource = new List<Person> {
new Person("Sam", "Smith"),
new Person("Jim", "Henson"),
new Person("Betty", "White"),
};
}
XAML:
<ListBox HorizontalContentAlignment="Stretch" x:Name="MyListBox" >
<ListBox.ItemTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal" >
<Label Content="{Binding FirstName}"/>
<Label Content="{Binding LastName}"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Now when the Listbox displays, it will cycle through each of the items in the ItemsSource property, and then lay them out using the DataTemplate. It's possible to have the DataTemplate target specific classes by using the DataType property if you're using polymorphism (as in different types of people such as 'Cusomters' or 'Employees' which all derive from 'Person).
The problem with this approach is that you are setting the value of the items directly, which is bad form. It's better to define a class that handles all of the data for your view separately. Consider:
public class ViewModel {
// WPF will automatically read these properties using reflection.
public List<Person> People {
get {
return new List<Person> {
new Person("Sam", "Smith"),
new Person("Jim", "Henson"),
new Person("Betty", "White")
};
}
}
}
That will hold all the data for the view, now let's add it to the actual window. First we need to reference the namespace ('xmlns' means xml namespace):
<Window x:Class="Sharp.MyWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:lol="clr-namespace:Sharp">
The namespace is Sharp (the namespace where my stuff lives), and the alias we'll give it is lol. Now we attach our ViewModel class to the window by setting it to the DataContext property, as in:
<Window>
<Window.DataContext>
<lol:ViewModel />
</Window.DataContext>
</Window>
This makes all of the public properties on the ViewModel class available to the Window. This way, if we want to read the Persons information into our ListBox, we simply say:
<ListBox HorizontalContentAlignment="Stretch" ItemsSource="{Binding People}" >
...
</ListBox>
Notice that we say ItemsSource={Binding People}, which means 'scan the ViewModel for any public properties called 'People' and then retrieve those results. This is essentially the fundamentals behind the MVVM approach. You might have all of your business logic in one or many classes which handle the main application operation in a Model, but then you have a ViewModel which interacts with the Model and exposes the results as public properties. WPF automatically binds to those properties and presents them for your. The information just flows, rather than setting the values by force.
To really understand how WPF is supposed to work, you should take some time to understand the basics of MVVM. WPF was really designed with MVVM in mind, and so to really get how WPF is supposed to work, you really should take the time to get your head around it. Take a look at:
http://agilewarrior.wordpress.com/2011/01/11/simple-mvvm-walkthrough-part-i/ .

<ListBox ItemsSource="{Binding QueryResults}">
<ListBox.ItemsTemplate>
<DataTemplate>
<StackPanel Orientation="Horizontal">
<Image Source="{Binding ImageSource}"/>
<TextBlock Text="{Binding TextSource}"/>
</StackPanel>
</DataTemplate>
</ListBox.ItemsTemplate>
</ListBox>
Will work if you have a list of objects named QueryResults in your code behind. Each object needs to have an string property named ImageSource and a string property named TextSource.
However, since you only need to display a green circle icon for each of the items, you can hardcode the image source. The above will work if you want to have a different icon for each, though.
Also note that in order for this to work, you need to set the DataContext of the window to DataContext="{Binding RelativeSource={RelativeSource Self}}"

Populate WPF DataGrid dynamically

My program needs to take input from a fire alarm panel over a serial connection and populate a list based on it. When a new device is reported from the panel, the statement is parsed and the device is added to the device List.
That part of my program all works fine and dandy. The problem now is displaying the list of fire alarm devices to the user.
I am hoping to do this using a DataGrid (unless there's a better way?) but am not able to find a lot of helpful documentation on WPF DataGrids that is relevant to me. Most of what's out there seems to be displaying data from a database. Mine however, needs to update every time the panel spits out a new device description and the device List in my program is appended.
I see I can set AutoGenerateColumns to true and initially display my list just fine. BUT, I would like to customize the column headers. Also this doesn't update when the List is appended so I'm not sure how to "refresh" it.
When AutoGenerateColumns is false, I get no data displayed. When the program runs it shows me the correct number of rows corresponding to the number of items in my list, but no data. Wondering how/if I need to link each column with its corresponding device data member?
Lastly, how do you format a DataGrid to look pretty through re-sizes? I can set column width and all that, but what I want is a few of the columns to be fixed width, and the middle column to expand to fill remaining available area.
This is my first stab at WPF. Any help would be greatly appreciated!

Personaly i dont like DataGrid much. Yes they are easier to bind and they offer built-in resize and sorting options but they are not as flexible as an ItemsControl with a good DataTemplating on your Objects. Let me explain myself.
I tend to populate my ItemsControl with an ObservableCollection. Then, i use a DataTemplate in order to tell my ItemsControl how to display my custom items.
Your CustomObjects can be Modeles objects if your doing MVVM.
If your list is binded to an ObservableCollection, the Added and Removed items will appear dynamicly into your list, which is what i belive your trying to do.
For the column size, you could put a Grid specifying GridColumns width to fixed Width for some columns and * for others so they fill the remaining space.
Here's an alternative to the GridView
I use a ScrollViewer around my ItemControl so if the ItemsControl get too big, you can scroll it.
The ItemsControl's ItemSource is binded to your FireAlarms's ObservableCollection.
The WrapPanel in the ItemsControl will contain each DataTemplate. It's Width is binded to his parent (or ancestor if you will) which is an ItemsControl
<ScrollViewer
Grid.Row="x"
Grid.Column="y"
VerticalScrollBarVisibility="Auto"
Margin="5">
<ItemsControl
BorderBrush="DarkBlue"
BorderThickness="2"
ItemsSource="{Binding Path=FireAlarms}"
ItemTemplate="{StaticResource FireAlarmsTemplate}"
>
<ItemsControl.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel
Orientation="Horizontal"
Width="{Binding RelativeSource=
{RelativeSource FindAncestor,
AncestorType={x:Type ItemsControl}},
Path=ActualWidth}"
>
</WrapPanel>
</ItemsPanelTemplate>
</ItemsControl.ItemsPanel>
</ItemsControl>
</ScrollViewer>
Ok then you need a DataTemplate. You can put the DataTemplate in your windows's ressource or in a DataDictionnary. Lets say you have a class :
FireAlarm
{
Public String AlarmInfo1;
Public String AlarmInfo2;
Public String AlarmInfo3;
}
Here could be a nice DataTemplate to start with :
<DataTemplate x:Key="FireAlarms">
<Border
BorderBrush="SteelBlue"
Background="LightBlue"
BorderThickness="2"
Margin="10"
Padding="10">
<StackPanel
Orientation="Vertical"
>
<Grid>
<Grid.RowDefinitions>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
<RowDefinition></RowDefinition>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition></ColumnDefinition>
<ColumnDefinition Width="5"></ColumnDefinition>
<ColumnDefinition></ColumnDefinition>
</Grid.ColumnDefinitions>
<Label
Grid.ColumnSpan="3"
Grid.Row="0"
Content="{Binding Path=AlarmName}"
Margin="5,-5,5,10"
FontWeight="Bold"
FontSize="16"
HorizontalContentAlignment="Center"
HorizontalAlignment="Center">
</Label>
<TextBlock
Text="Alarm information 1" Grid.Row="1" Grid.Column="0" />
<TextBox
Text="{Binding Path=AlarmInfo1}"
Grid.Column="2"
Grid.Row="1"
>
</TextBox>
<TextBlock
Text="Alarm information 2" Grid.Row="2" Grid.Column="0" />
<TextBox
Text="{Binding Path=AlarmInfo2}"
Grid.Column="2"
Grid.Row="2"
>
</TextBox>
<TextBlock
Text="Alarm information 3" Grid.Row="3" Grid.Column="0" />
<TextBox
Text="{Binding Path=AlarmInfo3}"
Grid.Column="2"
Grid.Row="3"
>
</TextBox>
</Grid>
</StackPanel>
</Border>
</DataTemplate>
Ok I hope this is usefull for you. My Template will generate 1 square per alarm. If you'd rather have it in a Table like a GridView, you could modify this using a verticaly oriented stack panel and use a grid with variable // invariable column width but since you asked for anything usefull, i tough i'd guive you something fun to work with!
Enjoy!

Some time back I wrote a post Create DataGrid in WPF using code take a look at it, it will help you in creating data grid in dynamic scenarios like yours

If you a dynamic grid (meaning the number and design of the columns are unknown at design time), I do it with code-behind with binding. I generally use the MVVM pattern (if you not familiar with this, I really recommend reading into it since it is THE pattern when working with WPF).
1) You have to set Auto-Generate columns to false of course and give grid a name (here myDataGrid)
GridViewDataColumn newColumn= new GridViewDataColumn();
myDataGrid.Columns.Add(newColumn)
This will add the column to your grid. Now the column will be empty. Now it depends on your data how to fill it with data. If you bind to a known property on the items, do:
newColumn.Binding = new Binding("knownPropertyName");
In most cases though, you do not know the propertyname and bind to an element in the collection.
Then it would like more:
myDoubleCollection.Add(someDoubleValue); //do this for each item in the itemssource of the grid
int index=myDoubleCollection.Count-1;
newColumn.Binding = new Binding(string.Format("myDoubleCollection[{0}]",index));
So this works also.
Another thing to keep in mind is the deletion of columns. This requires some extra work.

That's a lot of questions rolled into one! I suggest you do a bit more background research before asking questions. I would recommend that your read this codeproject article I wrote about the WPF DataGrid a while back:
http://www.codeproject.com/KB/WPF/WPFDataGridExamples.aspx
It will answer most of your questions for you!

Take a look at the MVVM pattern, it'll be a huge help as you create this application.
What you want is an ObservableCollection in the ViewModel. You'll bind the ItemsSource property of the datagrid to this collection. Then have your columns bind to various properties on to display them. Whenever this ObservableCollection has an item appended, your front end should update automatically.
To have a column autosize, set the Width="*".
Here's a sample of a datagrid with MVVM
<DataGrid ItemsSource="{Binding FireAlarmCollection}" SelectedItem="{Binding SelectedFireAlarm, Mode=TwoWay}" AutoGenerateColumns="True" CanUserSortColumns="True" HorizontalScrollBarVisibility="Visible" CanUserResizeColumns="True">
</DataGrid>
As you continue your effort, post separate questions for each issue.

Binding ListBox to List (Collection) in XAML

I'm learning WPF, so I'm kind of n00b in this.
I saw some examples about how to do what I want to do, but nothing exactly...
The question: I want to bind List to ListBox. I want to do it in XAML, w/o coding in code behind. How can I achieve that?
Right now I do it that way:
XAML
<ListBox x:Name="FileList">
<ListBox.ItemTemplate>
<DataTemplate>
<Label Content="{Binding Path=.}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
Code behind
public MainWindow()
{
// ...
files = new List<string>();
FileList.ItemsSource = files;
}
private void FolderBrowser_TextChanged(object sender, RoutedEventArgs e)
{
string folder = FolderBrowser.Text;
files.Clear();
files.AddRange(Directory.GetFiles(folder, "*.txt", SearchOption.AllDirectories));
FileList.Items.Refresh();
}
But I want to get rid of FileList.ItemsSource = files; and FileList.Items.Refresh(); in C# code.
Thanks

First, setup the binding in your listbox:
<ListBox x:Name="FileList" ItemsSource="{Binding Files}">
<ListBox.ItemTemplate>
<DataTemplate>
<Label Content="{Binding Path=.}"/>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
or
<ListBox x:Name="FileList" ItemsSource="{Binding Files}" DisplayMemberPath="."/>
Next, make sure "Files" is a property in your DataContext (or code behind). (You can't bind to fields, only properties...)
Ideally, you'll want to make Files an ObservableCollection<T> instead of a List<T>, as well. This will allow the binding to handle adding or removing elements correctly.
If you do these two things, it should just work correctly.

Two tricks to add to Reed's answer:
1) If all you're displaying in your list box items is a string, you can avoid the ListBox.ItemTemplate folderol by just setting ListBox.DisplayMemberPath.
2) You can set the window's DataContext to itself. For instance, give the window a name of MyWindow and set its DataContext to {Binding ElementName=MyWindow}. Now you can bind to any of its public properties. (I'm pretty sure Reed's who I learned that trick from in the first place.)